Field of the Invention
Embodiments of the present invention generally relate to a method of removing film layers from a substrate.
Description of the Related Art
Devices, such as OLEDs, use passivation layers to increase the useful life of the device. Passivation layers can be deposited by chemical vapor deposition (CVD). As the deposition of a film by CVD is generally non-specific, layers of film may form on areas of the substrate where they are not desired, such as the formation of a passivation layer over certain metal features. As such, access to metal layers may be important to the sequential creation of other devices on the same substrate.
During processing, removal of specific areas of film may occur. Techniques for the removal of specific areas of film include masking and etching and laser-based techniques. Masking and etching involves utilization of masks oftentimes made of photoresists. Photoresists are exposed to specific wavelengths of radiation. The exposed portions of the photoresists are removed during a development process to leave portions of the surface to be etched exposed. Pulsed laser sources have been used to perform laser-based material processing for applications such as ablation and delamination of deposited films.
While masking and etching can be used to remove specific surface areas, masking and etching can be cost prohibitive. Laser ablation can be targeted to specific areas of the film to destroy the film in those areas. However, by destroying the layer, laser ablation creates undesirable debris and remnants which must be cleared from the chamber before continuing processing. Related art delamination techniques destroy the layer from under the surface which can create similar debris as standard ablation techniques. Further, specificity of delamination on the substrate may be limited as it is difficult to target specific areas based on the size of the feature.
Thus, there is a need in the art for methods of film removal which are targeted for removal of specific areas of a film while controlling the separation of film.